Opisthocomus hoazin

Fascinating Facts

  • Chicks have large claws on each wing, leading some scientists to link the species with the fossil Archaeopteryx.
  • Chicks can also swim; they will drop into rivers to escape predators.
  • They are the only bird with a digestive system that ferments vegetation similar to a cow.
  • They have a callused skin patch on their sternum where they rest their swollen gut (from the fermenting plant material).
  • Hoatzins live in groups of 15-100 birds.


Swamps, forests, and freshwater mangroves. They exclusively eat swamp plants (leaves, roots, and flowers), enabled by their enlarged crop which ferments their food before entering the gut. They are also called “stinkbirds” because this process creates an unpleasant odor similar to cow manure.

Status in the Wild

Least Concern – IUCN 2012


South America, mostly in the Amazon and Orinoco river basins.

Location in the Zoo

Reptiles and Birds Zone of the Sculpture Learning Plaza

Animals & Exhibits